The present invention relates generally to the field of electrical enclosures, such as enclosures for motor control centers used in industrial and commercial settings. More particularly, embodiments of the present invention relate to electrical enclosures designed with a remote temperature monitoring system.
Electrical enclosures and cabinets can be used in a wide range of industrial and automation applications. The enclosures are configured to support electrical circuitry and electrical components therein, and to receive and send electrical power and data signals. For example, the enclosures can be employed to house various power electronics equipment, control circuits, motor drives, and so forth. Within the industry, it is not uncommon to find the enclosures divided into individual segments and bays that house electrical components, such as single and three-phase switches, motor controllers, programmable automation controllers, data and power network interfaces, and so forth. Because the electrical components within the enclosure function in a high voltage environment, doors are used to control and regulate access to the interior of the individual bays or segments during operation of the enclosures.
In some situations, electrical faults within the enclosure can cause sudden pressure increases and/or localized heating (e.g., hot spots). For example, localized heating within the enclosure may damage wires, insulation, components, and even the structure of the enclosure. Moreover, localized heating within the enclosure can lead to increased costs due to lost production time and system failures. However, it is difficult to continuously (e.g., during operation) monitor a closed electrical enclosure for localized heating. For example, it is difficult to examine the dark interior of a closed electrical enclosure to determine the location of the localized heating while the system is in normal operation mode. Moreover, when a system is believed or known to be experiencing faults, considerable time may be involved in donning and doffing appropriate gear to open the enclosures for manual verification and servicing. In virtually all cases, it would be preferred to avoid such service until and unless it is actually required. Still further, techniques have been proposed for detecting arcflash events in enclosures, but these are typically extremely hot, and so can be detected directly. Heating that does not or that does not necessarily result in arcing is simply undetectable by such approaches. Accordingly, there is a need for cost-effective techniques for remotely monitoring abnormal temperatures (e.g., localized heating or hot spots) within a closed electrical enclosure in real-time.